Piston



' A. J. BOCKWITZ I Feb. 24. 1925.

PISTON Filed Oct. 19, 1920 Patented Feb. 24, 1925.

UNITED STATES PAT EINT, i oFFIcE.

ANDREW J. BOOKWITZ, OF TWIN FALLS, IDAHO.

PISTON.

Application filed October 19, 1920. Serial No. 417,927.

tons whether those of steam, air, and gas engines or pumps, my object being, at all times, notwithstanding wear, to maintain I tight joints with a minimum of friction on and wear of the cylinder walls, thus securing a maximum efficiency with .minimu waste of energy and wear of parts.

In the accompanying drawingsi Fig. 1 is a view partly in Vertical section and partly in side elevation of enough of a gas engine piston to illustrate one form of my invention;

Fig. 2 is a similar view of another embodiment of my invention.

Briefly described, my invention contemplates the use of two or more split metal rings placed side by side in an annular groove in the periphery of clined surfaces on groove wall and adjacent ring, the inclination of the groove wall being undercut so that by the radial expansion of the contactin ring the latter willtend to move axially o the cylinder and thus result in tight contact of the inclined surfaces against one another and alsoof abutting surfaces of adjacent rings.

Describin with more detail what is shown in t e accompanying drawings to exemplify my invention and referring in particular to Fig. l, the piston, 10 ,has an annular groove, 11, in 1ts circumference, 'both of whose opposite walls are inclined outward and towards each other, and 1n such groove there are two similar split spring rings, 12, s aced apart with adjacent faces parallel an with their faces next the inclined wall of the groove correspondingly inclined so that any outward expansion of said rings, 12, results in movement or tendency a piston with inof movement towards ring, 13, of ordinary construction placed between them. The outer peripheries of the rings, 12, areof the same diameter as that of the ring, 13, so that all three rings have contact with the cylinder wall and thus afford an extended continuous surface. As wear of-the packing ring, 13, takes place it expands outward to maintain its contact with-the cylinder wall but at all times it is pressed against its opposite sides by the expanding action of the rings, 12.

In the form of my invention shown. in Fig. 2, I employ but one ring, 120, corresponding-to annular groove, 111, in piston, 110, has but one inclined surface so that the expanding packing ring, 130, with opposite sides paral: lel fits. between the adjacent parallel wall of the groove, 111, and the adjacent parallel surface of the r'in 130. The construction and action of the parts in other respects are thesame as in the Fig. 1.

It,'of course, is to be understood that I do 75 not limit myself to any particular angle of inclination of abutting surfaces of r ng and piston groove.

Preferably the cylinder'engaging periphcry of the rings with inclined faces is less than the cylinder engaging surfaces of the other'ring which latter maybe regarded as the packing ring proper.

e rings can be of eccentric or concentric construction.

WhatI claim is:

A piston packing comprisingan annular groove in the periphery of the piston, a plurality of rings in such groove with peripheries that contact with the cylinder, the

groove and certain of said rings having inclined contacting surfaces, and a ring intermediate the rings with the inclined surfaces with its opposite sides in planes at r ght angles to the cylinder axis. I

In testimony whereof I hereunto afiix my signature.

ANDREWJ. ooKwITz.

one another and upon an interposed packing the ring, 12,'of"Fig. 1-, and the.

case as what is shown in 

